From what I know of NI stuff, having used similar hardware in my old lab, they tend to be purpose-built, so, without a GC/MS, they likely aren't useful for much of anything.

However, for someone that has a GC/MS and has a card that died, or wants to get one up and running and has the Mac, but no cards, they are worth their weight in gold, since finding old, specific interface cards like that can be extremely difficult, bordering on impossible (I have found that out the hard way when old lab hardware went south and replacements were no where to be found...)

So, they likely have an unbelievably small market, but to the right buyer, they'll sacrifice their children to get one.